长链非编码RNA ENST00000454471对关键基因表达的调控在结直肠癌发生发展中的作用及机制

Several studies have indicated that long non-coding RNA (lncRNA) may play an important role in tumorigenesis and progression of colorectal caner (CRC), but the underlying mechanisms remain elusive. In addition, a lot of related lncRNAs have not been revealed due to the variety and complexity. Our preliminary studies: ①screened lncRNAs expression profile in the normal epithelium, adenoma, and CRC tissues using high throughput microarrays, and identified ENST00000454471 as a distinguishing lncRNA closely associated with tumorigenesis;②ENST00000454471 knock-down suppressed tumor proliferation, migration and invasion, while induced tumor apoptosis. In this study, we aim to:①retro-regulate the expression of ENST00000454471 and investigate its role on malignant activity in both adenoma and adenocarcinoma cells;②screen the interacted proteins and specific DNA banding loci of ENST00000454471 using expression profile microarrays, CHIRP-Seq, RNA pull down, CHIP and other approaches; thus, clarify the underlying molecular mechanisms of ENST00000454471 on gene expression; ③ establish and validate a prediction model based on the expression level of ENST00000454471. This study could further provide a potential molecular marker and therapeutic target for prevention, early detection and treatment of CRC.

有研究提示多个长链非编码RNA(lncRNA)与结直肠癌发生发展相关，但其调控机制远未阐明。同时仍有大量相关lncRNA未被发现。我们前期：①通过高通量芯片在“正常-腺瘤-进展期癌”中筛选并验证出了ENST00000454471这一特征性差异表达的lncRNA；②功能实验揭示ENST00000454471可促进腺癌细胞增殖、迁移和侵袭，抑制凋亡。在此基础上，我们拟：①在结肠腺瘤和腺癌细胞中，反向调控ENST00000454471表达，体内外实验观察对肿瘤恶性行为能力的影响；②应用表达谱芯片、CHIRP-Seq、RNA pull down 、CHIP和高通量测序等技术，探索ENST00000454471相互作用的关键蛋白和特异基因结合位点，绘制出其调控键基因表达的分子信号网络图；③以ENST00000454471表达构建预后预测模型。由此为肿瘤预防和早诊早治提供新的分子标记及潜在治疗靶点。

研究背景：有研究提示多个长链非编码RNA（lncRNA）与结直肠癌发生发展相关，但其调控机制远未阐明。同时仍有大量相关lncRNA未被发现。我们前期：1）通过高通量芯片在“正常-腺瘤-进展期癌” 中筛选并验证出了ENST00000454471这一特征性差异表达的lncRNA；2）功能实验揭示ENST00000454471可促进腺癌细胞增殖、迁移和侵袭，抑制凋亡，但其具体机制尚不清楚。.研究目的：阐明lncRNA ET471在结直肠癌侵袭转移中扮演的角色及相关分子机制。.主要研究结果：①lncRNA ET471在“正常结直肠上皮-腺瘤-腺癌”这一经典的肠癌发病过程表达呈逐渐上升趋势；体内外研究显示ET471可促进结直肠癌生长和侵袭。②与非肿瘤组织相比，在结直肠腺瘤和癌中，miR-214的表达水平显著下调，ET471和miR-214之间有明显的负相关性，体内外研究显示miR-214通过负调控lncRNA ET471表达，从而调节结直肠肿瘤的侵袭转移。③生物素-亲和素拉下试验等研究结果示miR-214通过竞争ET471序列中的miRNA结合位点抑制结直肠肿瘤进展，提示了miR-214在调控网络中可能的作用机制。.结论及意义：本项目证实了lncRNA ET471可促进结直肠肿瘤的生长和侵袭，miR-214通过负调控lncRNA ET471表达，从而调节结直肠肿瘤的侵袭转移，并通过竞争ET471序列中的miRNA结合位点抑制结肠肿瘤进展。该成果有望作为结直肠癌预防和靶向干预的靶点。